This invention relates to electric and gas powered weed and brush trimmers. More particularly, this invention relates to such trimmers adapted for alternately serving as a grass and debris blower.
The adaptation of a weed cutting or trimming implement to alternately or simultaneously blow grass and debris is taught by U.S. Pat. No. 5,345,788 issued Sep. 13, 1994, to Jerry; disclosing a steel blade having air driving fins protruding therefrom. A similar adaptation of a grass or weed cutting blade is taught by U.S. Pat. No. 5,233,820 issued Aug. 10, 1993, to Willsie. In another expression of the concept, U.S. Pat. No. 4,827,702 issued May 9, 1999, teaches a rotatable flexible line trimmer having a fan blade ring removably attached to its rotatable trimmer head. Adaptations of weed or grass cutting blades to propel air for debris removal are undesirable because the air propelling function dissipates power needed for cutting. Adaptations of line trimmer heads to include attachable and detachable air propelling blades are similarly undesirable because detachable fan blades may be lost or misplaced, and attachment and detachment steps are inconvenient and cumbersome.
The instant invention overcomes the disadvantages described above by providing a weed trimmer head having alternately extendable and retractable fan blades; the trimmer head thereby allowing, upon retraction of the fan blades, full rotary power to be applied to a weed cutting element; and alternately allowing, upon extension of the fan blades, air sweeping of debris from sidewalks and curbs.
The instant inventive trimmer-blower preferably comprises a cylindrical housing having an upper wall or ceiling spanning across its upper end. The upper surface of the upper wall is preferably adapted for attachment to the drive linkage of an electric or gasoline powered handheld or shoulder mounted weed and grass trimmer. Where the drive linkage of such trimmer comprises a spirally threaded lug, an internally spirally threaded nut embedded axially within and extending upwardly from said upper wall is preferably utilized as the attaching means. A steel ring or collar, through which a threaded bolt upwardly passes, may alternately be utilized where the trimmer includes a female drive linkage.
The above described cylindrical rotatable housing preferably defines a downwardly opening cylindrical space within which at least two fan blades are slidably mounted for alternate outward extension and inward retraction. Preferably, slide channels for guiding the fan blades"" outward extension and inward retraction are fixedly situated within the housing. Also preferably, the channels comprise a series of slide stopping or slide resisting walls and ridges for selectively holding the fan blades in their extended or retracted positions within the housing.
Preferably, the downward opening of the cylindrical space is closed by a removably attached lower wall, the upper surface of such lower wall providing lower slide surfaces of the slide channels.
Preferably, the housing has weed trimmer line or blade extending means integral with the lower wall or lower side wall of the housing; such means being positioned below the blades, allowing the implement to be alternately utilized for grass and debris blowing and for weed trimming.
Accordingly, it is an object of the present invention to provide a rotatable weed trimmer head which is adapted for alternately blowing grass clippings and debris.
It is a further object of the present invention to provide such an implement having alternately extendable and retractable air propelling fan blades.
Other and further objects, benefits, and advantages of the present invention will become known to those skilled in the art upon review of the Detailed Description which follows, and upon review of the appended drawings.